<!DOCTYPE html>
<html lang="en">
<head>
    <meta charset="UTF-8">
    <meta name="viewport" content="width=device-width, initial-scale=1.0">
    <meta http-equiv="X-UA-Compatible" content="ie=edge">
    <title>Document</title>
    <style>
        .banner{
            width: 500px;
            margin: 0 auto;
            text-align: center;
        }
        .banner img{
            width:100%;
            height: 300px;
            object-fit: contain;
            border: 1px solid;
            display: block;
        }
    </style>
</head>
<body>
    <div class="banner">
        <img src="img/1.jpg" alt="">
        <p>
            <button>上一张</button>
            <button>下一张</button>
        </p>
    </div>
</body>
</html>
